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Posted to commits@hbase.apache.org by gi...@apache.org on 2017/12/01 15:18:39 UTC

[24/50] hbase-site git commit: Published site at .

http://git-wip-us.apache.org/repos/asf/hbase-site/blob/a5c4dca3/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.html
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diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.html b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.html
index 1e0d2de..95a9f97 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/wal/AsyncFSWAL.html
@@ -27,715 +27,733 @@
 <span class="sourceLineNo">019</span><a name="line.19"></a>
 <span class="sourceLineNo">020</span>import static org.apache.hadoop.hbase.io.asyncfs.FanOutOneBlockAsyncDFSOutputHelper.shouldRetryCreate;<a name="line.20"></a>
 <span class="sourceLineNo">021</span><a name="line.21"></a>
-<span class="sourceLineNo">022</span>import java.io.IOException;<a name="line.22"></a>
-<span class="sourceLineNo">023</span>import java.io.InterruptedIOException;<a name="line.23"></a>
-<span class="sourceLineNo">024</span>import java.lang.reflect.Field;<a name="line.24"></a>
-<span class="sourceLineNo">025</span>import java.util.ArrayDeque;<a name="line.25"></a>
-<span class="sourceLineNo">026</span>import java.util.Comparator;<a name="line.26"></a>
-<span class="sourceLineNo">027</span>import java.util.Deque;<a name="line.27"></a>
-<span class="sourceLineNo">028</span>import java.util.Iterator;<a name="line.28"></a>
-<span class="sourceLineNo">029</span>import java.util.List;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import java.util.Queue;<a name="line.30"></a>
-<span class="sourceLineNo">031</span>import java.util.SortedSet;<a name="line.31"></a>
-<span class="sourceLineNo">032</span>import java.util.TreeSet;<a name="line.32"></a>
-<span class="sourceLineNo">033</span>import java.util.concurrent.ExecutorService;<a name="line.33"></a>
-<span class="sourceLineNo">034</span>import java.util.concurrent.Executors;<a name="line.34"></a>
-<span class="sourceLineNo">035</span>import java.util.concurrent.atomic.AtomicBoolean;<a name="line.35"></a>
-<span class="sourceLineNo">036</span>import java.util.concurrent.locks.Condition;<a name="line.36"></a>
-<span class="sourceLineNo">037</span>import java.util.concurrent.locks.Lock;<a name="line.37"></a>
-<span class="sourceLineNo">038</span>import java.util.concurrent.locks.ReentrantLock;<a name="line.38"></a>
-<span class="sourceLineNo">039</span>import java.util.function.Supplier;<a name="line.39"></a>
-<span class="sourceLineNo">040</span><a name="line.40"></a>
-<span class="sourceLineNo">041</span>import org.apache.commons.logging.Log;<a name="line.41"></a>
-<span class="sourceLineNo">042</span>import org.apache.commons.logging.LogFactory;<a name="line.42"></a>
-<span class="sourceLineNo">043</span>import org.apache.hadoop.conf.Configuration;<a name="line.43"></a>
-<span class="sourceLineNo">044</span>import org.apache.hadoop.fs.FileSystem;<a name="line.44"></a>
-<span class="sourceLineNo">045</span>import org.apache.hadoop.fs.Path;<a name="line.45"></a>
-<span class="sourceLineNo">046</span>import org.apache.hadoop.hbase.HBaseInterfaceAudience;<a name="line.46"></a>
-<span class="sourceLineNo">047</span>import org.apache.hadoop.hbase.trace.TraceUtil;<a name="line.47"></a>
-<span class="sourceLineNo">048</span>import org.apache.yetus.audience.InterfaceAudience;<a name="line.48"></a>
-<span class="sourceLineNo">049</span>import org.apache.hadoop.hbase.client.ConnectionUtils;<a name="line.49"></a>
-<span class="sourceLineNo">050</span>import org.apache.hadoop.hbase.client.RegionInfo;<a name="line.50"></a>
-<span class="sourceLineNo">051</span>import org.apache.hadoop.hbase.io.asyncfs.AsyncFSOutput;<a name="line.51"></a>
-<span class="sourceLineNo">052</span>import org.apache.hadoop.hbase.io.asyncfs.FanOutOneBlockAsyncDFSOutputHelper.NameNodeException;<a name="line.52"></a>
-<span class="sourceLineNo">053</span>import org.apache.hadoop.hbase.wal.AsyncFSWALProvider;<a name="line.53"></a>
-<span class="sourceLineNo">054</span>import org.apache.hadoop.hbase.wal.WALEdit;<a name="line.54"></a>
-<span class="sourceLineNo">055</span>import org.apache.hadoop.hbase.wal.WALKey;<a name="line.55"></a>
-<span class="sourceLineNo">056</span>import org.apache.hadoop.hbase.wal.WALProvider.AsyncWriter;<a name="line.56"></a>
-<span class="sourceLineNo">057</span>import org.apache.hadoop.hbase.shaded.com.google.common.util.concurrent.ThreadFactoryBuilder;<a name="line.57"></a>
-<span class="sourceLineNo">058</span>import org.apache.hadoop.hbase.shaded.io.netty.channel.Channel;<a name="line.58"></a>
-<span class="sourceLineNo">059</span>import org.apache.hadoop.hbase.shaded.io.netty.channel.EventLoop;<a name="line.59"></a>
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-<span class="sourceLineNo">062</span>import org.apache.hadoop.ipc.RemoteException;<a name="line.62"></a>
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-<span class="sourceLineNo">065</span><a name="line.65"></a>
-<span class="sourceLineNo">066</span>import com.lmax.disruptor.RingBuffer;<a name="line.66"></a>
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-<span class="sourceLineNo">068</span>import com.lmax.disruptor.Sequencer;<a name="line.68"></a>
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-<span class="sourceLineNo">070</span>/**<a name="line.70"></a>
-<span class="sourceLineNo">071</span> * An asynchronous implementation of FSWAL.<a name="line.71"></a>
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-<span class="sourceLineNo">075</span> * For append, we process it as follow:<a name="line.75"></a>
-<span class="sourceLineNo">076</span> * &lt;ol&gt;<a name="line.76"></a>
-<span class="sourceLineNo">077</span> * &lt;li&gt;In the caller thread(typically, in the rpc handler thread):<a name="line.77"></a>
-<span class="sourceLineNo">078</span> * &lt;ol&gt;<a name="line.78"></a>
-<span class="sourceLineNo">079</span> * &lt;li&gt;Insert the entry into 'waitingConsumePayloads'. Use ringbuffer sequence as txid.&lt;/li&gt;<a name="line.79"></a>
-<span class="sourceLineNo">080</span> * &lt;li&gt;Schedule the consumer task if needed. See {@link #shouldScheduleConsumer()} for more details.<a name="line.80"></a>
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-<span class="sourceLineNo">085</span> * &lt;ol&gt;<a name="line.85"></a>
-<span class="sourceLineNo">086</span> * &lt;li&gt;Poll the entry from {@link #waitingConsumePayloads} and insert it into<a name="line.86"></a>
-<span class="sourceLineNo">087</span> * {@link #toWriteAppends}&lt;/li&gt;<a name="line.87"></a>
-<span class="sourceLineNo">088</span> * &lt;li&gt;Poll the entry from {@link #toWriteAppends}, append it to the AsyncWriter, and insert it into<a name="line.88"></a>
-<span class="sourceLineNo">089</span> * {@link #unackedAppends}&lt;/li&gt;<a name="line.89"></a>
-<span class="sourceLineNo">090</span> * &lt;li&gt;If the buffered size reaches {@link #batchSize}, or there is a sync request, then we call<a name="line.90"></a>
-<span class="sourceLineNo">091</span> * sync on the AsyncWriter.&lt;/li&gt;<a name="line.91"></a>
-<span class="sourceLineNo">092</span> * &lt;li&gt;In the callback methods:<a name="line.92"></a>
-<span class="sourceLineNo">093</span> * &lt;ul&gt;<a name="line.93"></a>
-<span class="sourceLineNo">094</span> * &lt;li&gt;If succeeded, poll the entry from {@link #unackedAppends} and drop it.&lt;/li&gt;<a name="line.94"></a>
-<span class="sourceLineNo">095</span> * &lt;li&gt;If failed, add all the entries in {@link #unackedAppends} back to {@link #toWriteAppends} and<a name="line.95"></a>
-<span class="sourceLineNo">096</span> * wait for writing them again.&lt;/li&gt;<a name="line.96"></a>
-<span class="sourceLineNo">097</span> * &lt;/ul&gt;<a name="line.97"></a>
-<span class="sourceLineNo">098</span> * &lt;/li&gt;<a name="line.98"></a>
-<span class="sourceLineNo">099</span> * &lt;/ol&gt;<a name="line.99"></a>
-<span class="sourceLineNo">100</span> * &lt;/li&gt;<a name="line.100"></a>
-<span class="sourceLineNo">101</span> * &lt;/ol&gt;<a name="line.101"></a>
-<span class="sourceLineNo">102</span> * For sync, the processing stages are almost same. And different from FSHLog, we will open a new<a name="line.102"></a>
-<span class="sourceLineNo">103</span> * writer and rewrite unacked entries to the new writer and sync again if we hit a sync error.<a name="line.103"></a>
-<span class="sourceLineNo">104</span> * &lt;p&gt;<a name="line.104"></a>
-<span class="sourceLineNo">105</span> * Here we only describe the logic of doReplaceWriter. The main logic of rollWriter is same with<a name="line.105"></a>
-<span class="sourceLineNo">106</span> * FSHLog.&lt;br&gt;<a name="line.106"></a>
-<span class="sourceLineNo">107</span> * For a normal roll request(for example, we have reached the log roll size):<a name="line.107"></a>
-<span class="sourceLineNo">108</span> * &lt;ol&gt;<a name="line.108"></a>
-<span class="sourceLineNo">109</span> * &lt;li&gt;In the log roller thread, we will set {@link #waitingRoll} to true and<a name="line.109"></a>
-<span class="sourceLineNo">110</span> * {@link #readyForRolling} to false, and then wait on {@link #readyForRolling}(see<a name="line.110"></a>
-<span class="sourceLineNo">111</span> * {@link #waitForSafePoint()}).&lt;/li&gt;<a name="line.111"></a>
-<span class="sourceLineNo">112</span> * &lt;li&gt;In the consumer thread, we will stop polling entries from {@link #waitingConsumePayloads} if<a name="line.112"></a>
-<span class="sourceLineNo">113</span> * {@link #waitingRoll} is true, and also stop writing the entries in {@link #toWriteAppends} out.<a name="line.113"></a>
-<span class="sourceLineNo">114</span> * &lt;/li&gt;<a name="line.114"></a>
-<span class="sourceLineNo">115</span> * &lt;li&gt;If there are unflush data in the writer, sync them.&lt;/li&gt;<a name="line.115"></a>
-<span class="sourceLineNo">116</span> * &lt;li&gt;When all out-going sync request is finished, i.e, the {@link #unackedAppends} is empty,<a name="line.116"></a>
-<span class="sourceLineNo">117</span> * signal the {@link #readyForRollingCond}.&lt;/li&gt;<a name="line.117"></a>
-<span class="sourceLineNo">118</span> * &lt;li&gt;Back to the log roller thread, now we can confirm that there are no out-going entries, i.e.,<a name="line.118"></a>
-<span class="sourceLineNo">119</span> * we reach a safe point. So it is safe to replace old writer with new writer now.&lt;/li&gt;<a name="line.119"></a>
-<span class="sourceLineNo">120</span> * &lt;li&gt;Set {@link #writerBroken} and {@link #waitingRoll} to false, cancel log roller exit checker<a name="line.120"></a>
-<span class="sourceLineNo">121</span> * if any(see the comments in the {@link #syncFailed(Throwable)} method to see why we need a checker<a name="line.121"></a>
-<span class="sourceLineNo">122</span> * here).&lt;/li&gt;<a name="line.122"></a>
-<span class="sourceLineNo">123</span> * &lt;li&gt;Schedule the consumer task.&lt;/li&gt;<a name="line.123"></a>
-<span class="sourceLineNo">124</span> * &lt;li&gt;Schedule a background task to close the old writer.&lt;/li&gt;<a name="line.124"></a>
-<span class="sourceLineNo">125</span> * &lt;/ol&gt;<a name="line.125"></a>
-<span class="sourceLineNo">126</span> * For a broken writer roll request, the only difference is that we can bypass the wait for safe<a name="line.126"></a>
-<span class="sourceLineNo">127</span> * point stage. See the comments in the {@link #syncFailed(Throwable)} method for more details.<a name="line.127"></a>
-<span class="sourceLineNo">128</span> */<a name="line.128"></a>
-<span class="sourceLineNo">129</span>@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)<a name="line.129"></a>
-<span class="sourceLineNo">130</span>public class AsyncFSWAL extends AbstractFSWAL&lt;AsyncWriter&gt; {<a name="line.130"></a>
-<span class="sourceLineNo">131</span><a name="line.131"></a>
-<span class="sourceLineNo">132</span>  private static final Log LOG = LogFactory.getLog(AsyncFSWAL.class);<a name="line.132"></a>
+<span class="sourceLineNo">022</span>import com.lmax.disruptor.RingBuffer;<a name="line.22"></a>
+<span class="sourceLineNo">023</span>import com.lmax.disruptor.Sequence;<a name="line.23"></a>
+<span class="sourceLineNo">024</span>import com.lmax.disruptor.Sequencer;<a name="line.24"></a>
+<span class="sourceLineNo">025</span><a name="line.25"></a>
+<span class="sourceLineNo">026</span>import java.io.IOException;<a name="line.26"></a>
+<span class="sourceLineNo">027</span>import java.io.InterruptedIOException;<a name="line.27"></a>
+<span class="sourceLineNo">028</span>import java.lang.reflect.Field;<a name="line.28"></a>
+<span class="sourceLineNo">029</span>import java.util.ArrayDeque;<a name="line.29"></a>
+<span class="sourceLineNo">030</span>import java.util.Comparator;<a name="line.30"></a>
+<span class="sourceLineNo">031</span>import java.util.Deque;<a name="line.31"></a>
+<span class="sourceLineNo">032</span>import java.util.Iterator;<a name="line.32"></a>
+<span class="sourceLineNo">033</span>import java.util.List;<a name="line.33"></a>
+<span class="sourceLineNo">034</span>import java.util.Queue;<a name="line.34"></a>
+<span class="sourceLineNo">035</span>import java.util.SortedSet;<a name="line.35"></a>
+<span class="sourceLineNo">036</span>import java.util.TreeSet;<a name="line.36"></a>
+<span class="sourceLineNo">037</span>import java.util.concurrent.ExecutorService;<a name="line.37"></a>
+<span class="sourceLineNo">038</span>import java.util.concurrent.Executors;<a name="line.38"></a>
+<span class="sourceLineNo">039</span>import java.util.concurrent.LinkedBlockingQueue;<a name="line.39"></a>
+<span class="sourceLineNo">040</span>import java.util.concurrent.ThreadPoolExecutor;<a name="line.40"></a>
+<span class="sourceLineNo">041</span>import java.util.concurrent.TimeUnit;<a name="line.41"></a>
+<span class="sourceLineNo">042</span>import java.util.concurrent.atomic.AtomicBoolean;<a name="line.42"></a>
+<span class="sourceLineNo">043</span>import java.util.concurrent.locks.Condition;<a name="line.43"></a>
+<span class="sourceLineNo">044</span>import java.util.concurrent.locks.Lock;<a name="line.44"></a>
+<span class="sourceLineNo">045</span>import java.util.concurrent.locks.ReentrantLock;<a name="line.45"></a>
+<span class="sourceLineNo">046</span>import java.util.function.Supplier;<a name="line.46"></a>
+<span class="sourceLineNo">047</span><a name="line.47"></a>
+<span class="sourceLineNo">048</span>import org.apache.commons.logging.Log;<a name="line.48"></a>
+<span class="sourceLineNo">049</span>import org.apache.commons.logging.LogFactory;<a name="line.49"></a>
+<span class="sourceLineNo">050</span>import org.apache.hadoop.conf.Configuration;<a name="line.50"></a>
+<span class="sourceLineNo">051</span>import org.apache.hadoop.fs.FileSystem;<a name="line.51"></a>
+<span class="sourceLineNo">052</span>import org.apache.hadoop.fs.Path;<a name="line.52"></a>
+<span class="sourceLineNo">053</span>import org.apache.hadoop.hbase.HBaseInterfaceAudience;<a name="line.53"></a>
+<span class="sourceLineNo">054</span>import org.apache.hadoop.hbase.client.ConnectionUtils;<a name="line.54"></a>
+<span class="sourceLineNo">055</span>import org.apache.hadoop.hbase.client.RegionInfo;<a name="line.55"></a>
+<span class="sourceLineNo">056</span>import org.apache.hadoop.hbase.io.asyncfs.AsyncFSOutput;<a name="line.56"></a>
+<span class="sourceLineNo">057</span>import org.apache.hadoop.hbase.io.asyncfs.FanOutOneBlockAsyncDFSOutputHelper.NameNodeException;<a name="line.57"></a>
+<span class="sourceLineNo">058</span>import org.apache.hadoop.hbase.trace.TraceUtil;<a name="line.58"></a>
+<span class="sourceLineNo">059</span>import org.apache.hadoop.hbase.wal.AsyncFSWALProvider;<a name="line.59"></a>
+<span class="sourceLineNo">060</span>import org.apache.hadoop.hbase.wal.WALEdit;<a name="line.60"></a>
+<span class="sourceLineNo">061</span>import org.apache.hadoop.hbase.wal.WALKey;<a name="line.61"></a>
+<span class="sourceLineNo">062</span>import org.apache.hadoop.hbase.wal.WALProvider.AsyncWriter;<a name="line.62"></a>
+<span class="sourceLineNo">063</span>import org.apache.hadoop.hdfs.protocol.DatanodeInfo;<a name="line.63"></a>
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+<span class="sourceLineNo">065</span>import org.apache.htrace.core.TraceScope;<a name="line.65"></a>
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+<span class="sourceLineNo">073</span><a name="line.73"></a>
+<span class="sourceLineNo">074</span>/**<a name="line.74"></a>
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+<span class="sourceLineNo">078</span> * &lt;p&gt;<a name="line.78"></a>
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+<span class="sourceLineNo">082</span> * &lt;ol&gt;<a name="line.82"></a>
+<span class="sourceLineNo">083</span> * &lt;li&gt;Insert the entry into 'waitingConsumePayloads'. Use ringbuffer sequence as txid.&lt;/li&gt;<a name="line.83"></a>
+<span class="sourceLineNo">084</span> * &lt;li&gt;Schedule the consumer task if needed. See {@link #shouldScheduleConsumer()} for more details.<a name="line.84"></a>
+<span class="sourceLineNo">085</span> * &lt;/li&gt;<a name="line.85"></a>
+<span class="sourceLineNo">086</span> * &lt;/ol&gt;<a name="line.86"></a>
+<span class="sourceLineNo">087</span> * &lt;/li&gt;<a name="line.87"></a>
+<span class="sourceLineNo">088</span> * &lt;li&gt;In the consumer task(executed in a single threaded thread pool)<a name="line.88"></a>
+<span class="sourceLineNo">089</span> * &lt;ol&gt;<a name="line.89"></a>
+<span class="sourceLineNo">090</span> * &lt;li&gt;Poll the entry from {@link #waitingConsumePayloads} and insert it into<a name="line.90"></a>
+<span class="sourceLineNo">091</span> * {@link #toWriteAppends}&lt;/li&gt;<a name="line.91"></a>
+<span class="sourceLineNo">092</span> * &lt;li&gt;Poll the entry from {@link #toWriteAppends}, append it to the AsyncWriter, and insert it into<a name="line.92"></a>
+<span class="sourceLineNo">093</span> * {@link #unackedAppends}&lt;/li&gt;<a name="line.93"></a>
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+<span class="sourceLineNo">095</span> * sync on the AsyncWriter.&lt;/li&gt;<a name="line.95"></a>
+<span class="sourceLineNo">096</span> * &lt;li&gt;In the callback methods:<a name="line.96"></a>
+<span class="sourceLineNo">097</span> * &lt;ul&gt;<a name="line.97"></a>
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+<span class="sourceLineNo">099</span> * &lt;li&gt;If failed, add all the entries in {@link #unackedAppends} back to {@link #toWriteAppends} and<a name="line.99"></a>
+<span class="sourceLineNo">100</span> * wait for writing them again.&lt;/li&gt;<a name="line.100"></a>
+<span class="sourceLineNo">101</span> * &lt;/ul&gt;<a name="line.101"></a>
+<span class="sourceLineNo">102</span> * &lt;/li&gt;<a name="line.102"></a>
+<span class="sourceLineNo">103</span> * &lt;/ol&gt;<a name="line.103"></a>
+<span class="sourceLineNo">104</span> * &lt;/li&gt;<a name="line.104"></a>
+<span class="sourceLineNo">105</span> * &lt;/ol&gt;<a name="line.105"></a>
+<span class="sourceLineNo">106</span> * For sync, the processing stages are almost same. And different from FSHLog, we will open a new<a name="line.106"></a>
+<span class="sourceLineNo">107</span> * writer and rewrite unacked entries to the new writer and sync again if we hit a sync error.<a name="line.107"></a>
+<span class="sourceLineNo">108</span> * &lt;p&gt;<a name="line.108"></a>
+<span class="sourceLineNo">109</span> * Here we only describe the logic of doReplaceWriter. The main logic of rollWriter is same with<a name="line.109"></a>
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